"Starting with hrev45522, address space layout randomization (ASLR) and data execution prevention (DEP) are available in Haiku. These two features, which have actually become a standard in any modern OS, make it much harder to exploit any vulnerability that may be present in an application running on Haiku, thus generally improving system security."

Sometimes security by obscurity actually does work and unless they have made a deal with some OEM to sell haiku boxes I don't really see a point in this other than filling in a checkbox on a list, i really don't.

Right now it might be useless. But having the feature on by default makes sure that applications run in such an environment (and don't make weird assumptions). Which can come in handy should the feature ever become crucial.